1. Field of the Invention
The present invention relates to an apparatus comprising at least one delivering device which can suck one or more kinds of liquids such as a plurality of reagents, samples or the like from respective vessels into respective probes and which can deliver the sucked liquids from the probes into reaction vessels.
2. Description of the Prior Art
The above described kind of delivering apparatus is used for an automatic chemical analytical apparatus or the like dealing with a much amount of samples and is intended to deliver reagents corresponding to respective samples and test informations (analytical items) into reaction vessels. In such kind of delivering apparatus, contamination of the samples and reagents must be eliminated as much as possible in order to prevent degradation of the accuracy in analysis.
As one of the solutions for the above mentioned problem, it has been proposed to provide a plurality of delivering apparatus corresponding to each reagent. Such construction, however, is very inconvenient in space and cost. As another solution, it has been well known to provide one delivering fluid system for a plurality of reagents. In this construction, one end of the fluid system is connected to a vessel containing a reagent, whereas the other end of the fluid system is connected to a vessel containing a sample. In addition, to the fluid system is connected one pump through a changeover valve, whereby the changeover valve is operative to suck the reagent, sample and simultaneously deliver both the sample and the reagent into a reaction vessel. In such well known apparatus, the fluid system is completely filled with the reagent, so that some reagent which has been sucked is not delivered and becomes useless. Moreover, the entire length of the flow path must be washed and cleaned whenever the kind of the reagent is changed. Furthermore, changeover mechanism and changeover operation of the valve is complex and hence the apparatus is not reliable in operation.
In a further well known apparatus described in Japanese Laid-Open and not examined Specification No. 5,790/79, reagent vessels are arranged on a turntable and the turntable is rotated in a given direction by a motor through a slip mechanism. When a vessel containing a desirous reagent arrives at a suction position, the turntable is electro-magnetically stopped so as to suck the reagent from the reagent vessel. The reagent vessels are preferably made small in size for the purpose of disposing them on the turntable. As a result, the reagent should be concentrated several tens times the concentration of the conventional reagent. Therefore, the reagent must be diluted by a diluent (for example, water) during the lapse of time from the step of sucking the reagent into the probe to the step of delivering the reagent into the reaction vessels. As a result, such means and step are necessarily added. Moreover, even when only one reagent is delivered, all the reagent vessels must always be rotated and stopped together with the turntable, so that a driving and stopping mechanism becomes necessarily large in size and complex in operation.